So-called "head-only" exposure chambers have increasingly replaced whole body exposure chambers for pharmaceutical testing. In such chambers, the head (and, in most instances, neck) of a rabbit, dog, or some other animal of interest is exposed for an extended period of time to a stream of air in which the pharmaceutical is entrained. Most known head only chambers, however, are relatively large devices. It is not uncommon, for example, for a head only chamber which accommodates eight dogs to occupy an area of about 144 square feet. Many of the known chamber designs also place undue physical stress on the animals employed.
Consequently, there remains a need in the art for head-only exposure chamber designs which are more compact and/or provide a greater level of comfort to the animals.